26
|
Wu WC, Chan CL, Wong YW, Cuijpers JP. A study on the influence of breathing phases in intensity-modulated radiotherapy of lung tumours using four-dimensional CT. Br J Radiol 2009; 83:252-6. [PMID: 19723769 DOI: 10.1259/bjr/33094251] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
During gated intensity-modulated radiotherapy (IMRT) treatment for patients with inoperable non-small cell lung cancer (NSCLC), the end-expiration (EE) phase of respiratory is more stable, whereas end-inspiration (EI) spares more normal lung tissue. This study compared the relative plan quality based on dosimetric and biological indices of the planning target volume (PTV) and organs at risk (OARs) between EI and EE in gated IMRT. 16 Stage I NSCLC patients, who were scanned by four-dimensional CT, were recruited and re-planned. An IMRT plan of a prescription dose of 60 Gy per respiratory phase was computed using the iPlan treatment planning system. The heart, spinal cord, both lungs and PTV were outlined. The tumour control probability for the PTV and normal tissue complication probability for all OARs in the EE and EI phases were nearly the same; only the normal tissue complication probability of the heart in EE was slightly lower. Conversely, the conformation number of the PTV, V20 of the left lung, V30 of both lungs, Dmax of the heart and spinal cord, V10 of the heart and D5% of the spinal cord were better in EE, whereas D(mean) of the PTV, V20 of the right lung and maximum doses of both lungs were better in EI. No differences reached statistical significance (p<0.05) except Dmax of the spinal cord (p=0.033). Overall, there was no expected clinical impact between EI and EE in the study. However, based on the practicality factor, EI is recommended for patients who can perform breath-hold; otherwise, EE is recommended.
Collapse
|
27
|
Sherina MS, Rampal L, Loh JW, Chan CL, Teh PC, Tan PO. Self-esteem and its associated factors among secondary school students in Klang District, Selangor. THE MEDICAL JOURNAL OF MALAYSIA 2008; 63:26-30. [PMID: 18935727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Self-esteem is an important determinant of psychological well-being that is particularly problematic during adolescent life stage. There is a correlation between low self-esteem and other social problems among today's adolescents. This study was conducted to determine the mean self-esteem score, and to determine the association between self-esteem and age, sex, race, religion, number of siblings, ranking among siblings, family function, parental marital status and smoking among adolescents aged 12 to 20-years-old. A cross sectional study design using random cluster sampling method was done. Four out of a total of 35 secondary schools in Klang District, Selangor were selected. Respondents consisted of individual students in selected classes from the four selected schools. Data was collected using a self-administered, structured, pre-tested questionnaire and was analyzed using the SPSS version 12.0. Out of 1089 respondents, 793 completed the questionnaire (response rate 73.82%). The overall mean self-esteem score was 27.65. The mean self-esteem score for males (27.99) was slightly higher than females (27.31). The differences in the mean scores by race were statistically significant. There was a statistically significant relationship between mean self-esteem scores and sex, age, race, religion, number of siblings, smoking and family function. There was no statistically significant difference between mean self-esteem score with parental marital status and with ranking among siblings. The overall mean self-esteem score was 27.65. Self-esteem was associated with sex, age, race, religion, number of siblings, smoking and family function.
Collapse
|
28
|
Gooneratne ML, Facer P, Knowles CH, Chan CL, Lunniss PJ, Scott SM, Anand P, Williams NS. Normalization of substance P levels in rectal mucosa of patients with faecal incontinence treated successfully by sacral nerve stimulation. Br J Surg 2008; 95:477-83. [DOI: 10.1002/bjs.5905] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Abstract
Background
Sacral nerve stimulation (SNS) may improve faecal incontinence by modulating rectal sensation. This study measured changes in the peripheral expression of various neural epitopes in response to SNS.
Methods
Rectal mucosal biopsies were taken from 12 patients before and after temporary SNS, and from ten responders at 90 days after permanent stimulation. Sections were immunostained for substance P, transient receptor potential vanilloid (TRPV) 1, vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP). Levels were compared with those in nine continent controls.
Results
Baseline levels of percentage area immunoreactivities of substance P (median 0·51 (95 per cent confidence interval 0·31 to 0·73) versus 0·13 (0·07 to 0·27) per cent; P < 0·001) and TRPV1 (0·76 (0·41 to 1·11) versus 0·09 (0·04 to 0·14) per cent; P < 0·001), but not of VIP (1·26 (0·37 to 2·15) versus 1·28 (0·39 to 2·17); P = 0·943), were significantly greater than in controls. Successful SNS resulted in a significant decrease in substance P immunostaining after temporary (0·15 (0·06 to 0·51) per cent; P = 0·051) and permanent (0·17 (0 to 0·46) per cent; P = 0·051) stimulation. Immunoreactivity of TRPV1, VIP, CGRP and neural markers showed no qualitative change.
Conclusion
Patients with faecal incontinence demonstrate normalization of raised rectal mucosal substance P levels following successful SNS.
Collapse
|
29
|
Chan K, Chui SH, Wong DYL, Ha WY, Chan CL, Wong RNS. Protective effects of Danshensu from the aqueous extract of Salvia miltiorrhiza (Danshen) against homocysteine-induced endothelial dysfunction. Life Sci 2005; 75:3157-71. [PMID: 15488895 DOI: 10.1016/j.lfs.2004.06.010] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2003] [Accepted: 06/14/2004] [Indexed: 12/19/2022]
Abstract
Homocysteine (Hcy) is a by-product of methionine metabolism. An imbalance of Hcy in the body may lead to hyperhomocysteinemia, a condition with elevated Hcy concentration in blood that may be one of the risk factors responsible for the development of several vascular diseases (thromboembolism, atherosclerosis, stroke, vascular diseases and dementia). Radix Salvia miltiorrhiza (Danshen), a well-known Chinese medicinal herb that can activate and improve blood microcirculation, is noticeable for its beneficial effect in treating cardiovascular diseases. The present study is to demonstrate the protective effect of Danshen extract against the homocysteine-induced adverse effect on human umbilical vein endothelial cell (HUVEC). Homocysteine (5 mM) not only decreased the cell viability but also caused the disruption of capillary-like structure formation in vitro. The protective effect of Danshen aqueous extract and its active compounds on endothelial cell function were demonstrated through an in vitro tube formation assay, which mimics the new blood vessel formation. To identify the active components in the aqueous extract of Danshen, the content was characterized by instrumental analysis using high performance liquid chromatography with diode array detector (DAD) and electrospray tandem mass spectrometry (ESI-MS/MS). Interestingly, Danshen extract and its pure compounds showed different effectiveness in protecting HUVEC against Hcy-induced injury according to the following descending order: Danshen aqueous extract, 3-(3,4-dihydroxy-phenyl)-2-hydroxy-propionic acid (Danshensu), protocatechuic acid, catechin and protocatechualdehyde. We believed that such findings might provide evidence in understanding the beneficial effects of Danshen on the cardiovascular system.
Collapse
|
30
|
Zhao Z, Lu J, Leung K, Chan CL, Jiang ZH. Determination of Patchoulic Alcohol in Herba Pogostemonis by GC-MS-MS. Chem Pharm Bull (Tokyo) 2005; 53:856-60. [PMID: 15997154 DOI: 10.1248/cpb.53.856] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Patchoulic oil, the volatile oil of Pogostemon cablin (Blanco) Benth. and the Chinese crude drug Herba Pogostemonis, is widely used in the cosmetic and oral hygiene industries. Patchoulic alcohol is commonly used as an indicator for the quality assessment of dried P. cablin. However, the complexity of the herbal constituents makes it difficult for using conventional gas chromatography (GC) for analytical purpose. The present study established an accurate, sensitive and reproducible method for the quality assessment of the dried patchouli herb based on patchoulic alcohol content. A gas chromatography-tandem mass spectrometry (GC/MS/MS) method has been successfully developed and demonstrated for the determination of patchoulic alcohol content in the samples of dried P. cablin. The developed method was found to be convenient and facile in particular to tackle the complicated matrix problems always encountered in the herbs which contain high level of essential oils.
Collapse
|
31
|
Abstract
BACKGROUND This topic had not been researched previously and the information gained could have implications for midwives working with Chinese women everywhere. AIMS To explore the specific childbirth expectations of Hong Kong Chinese first-time pregnant women. METHODS This was a cross-sectional descriptive survey study and a Chinese version of the Childbirth Expectations Questionnaire was used to collect data. The sample consisted of 186 first-time pregnant women who first attended the antenatal clinic at a large public hospital in a major geographical region of Hong Kong. RESULTS Results showed that the Chinese pregnant women, the majority of who had not attended childbirth education classes, had high expectations of support from both their partners and midwives during labour and delivery. Conversely, expectations toward their own ability to cope with pain were relatively low. In addition, the pregnant women expressed concerns about the severity of labour pain and indicated low expectations about minimal use of medical interventions during labour. CONCLUSIONS This study results add to the existing literature about childbirth expectations of first-time pregnant Hong Kong Chinese women. Midwife educators should incorporate the findings into childbirth education classes to help pregnant women develop realistic and positive expectations.
Collapse
|
32
|
Yam VW, Li CK, Chan CL, Cheung KK. Synthesis, structural characterization, and photophysics of dinuclear gold(II) complexes [(Au(dppn)Br)(2)](PF(6))(2) and [(Au(dppn)I)(2)](PF(6))(2) with an unsupported Au(II)-Au(II) Bond. Inorg Chem 2001; 40:7054-8. [PMID: 11754290 DOI: 10.1021/ic010744t] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of novel dinuclear gold(II) complexes having an unsupported Au(II)-Au(II) bond with well-defined oxidation state at the gold center were synthesized. Red shifts in both the low-energy absorption and emission bands were observed upon increasing the donor ability of the coordinated halogen atoms.
Collapse
|
33
|
Chan CL, Meyer FJ, Hay RJ, Burnand KG. Toe ulceration associated with compression bandaging: observational study. BMJ (CLINICAL RESEARCH ED.) 2001; 323:1099. [PMID: 11701575 PMCID: PMC59685 DOI: 10.1136/bmj.323.7321.1099] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
34
|
Yu CL, Fielding R, Chan CL, Sham JS. Chinese nasopharyngeal carcinoma patients treated with radiotherapy: association between satisfaction with information provided and quality of life. Cancer 2001; 92:2126-35. [PMID: 11596029 DOI: 10.1002/cncr.1554] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Nasopharyngeal carcinoma (NPC) is highly prevalent in southern China. Prominent acute side effects of radiotherapy create problems in daily living and working that can generate considerable financial difficulties. A better adjustment to a diagnosis of NPC appears to be associated with an improved rate of recovery, a better quality of life (QoL), a quicker return to work, and normal functioning. Patient satisfaction with physician consultation and the way information is provided in particular may have significant bearing on QoL. The current study reports on short-term QoL after radiotherapy in NPC patients as a function of satisfaction with the information provided. METHODS Newly referred Hong Kong Chinese NPC patients (n = 211) completed interview measures at baseline before the initiation of radiotherapy, at 4 months after baseline (immediate posttreatment consultation) (FU 1), and again at 8 months (short-term postradiation period) after baseline (FU 2). Satisfaction with the information provided was measured by five items selected from the cognitive subscale of the Medical Interview Satisfaction Scale (MISS). QoL was measured by the Chinese version of the Functional Assessment of Cancer Therapy-General Scale (FACT-G (Ch)). RESULTS After adjustment for overall patient satisfaction (the PSQ-9), optimism, worry about family, anger, eating ability, subjective health, family income, and occupation at FU 1, treatment between baseline and FU 1, and disease recurrence after baseline, the 5-item MISS at FU 1 (beta = 0.21, P < 0.01) was found to significantly predict patient QoL at FU 2. Adjustment for baseline QoL and disease stage did not appear to alter this relation (beta = 0.20, P < 0.01). CONCLUSIONS To the authors' knowledge, there is very little research concerning NPC. The results of the current study reinforced the need to improve physicians' information provision during consultations with Chinese NPC patients shortly after the end of treatment.
Collapse
|
35
|
Chan CL, Gross CA. The anti-initial transcribed sequence, a portable sequence that impedes promoter escape, requires sigma70 for function. J Biol Chem 2001; 276:38201-9. [PMID: 11481327 DOI: 10.1074/jbc.m104764200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The anti-sequence, a portable element extending from +1 to +15 of the transcript, is sufficient to prevent promoter escape from a variety of strong final sigma70 promoters. We show here that this sequence does not function with even the strongest final sigma32 promoter. Moreover, a particular class of substitutions in final sigma70 that disrupt interaction between Region 2.2 of final sigma70 and a coiled-coiled motif in the beta'-subunit of RNA polymerase antagonizes the function of the anti-element. This same group of mutants prevents lambdaQ-mediated anti-termination at the lambdaP(R') promoter. At this promoter, interaction of final sigma70 with the non-template strand of the initial transcribed sequence (ITS) is required to promote the pause prerequisite for anti-termination. These mutants prevent pausing because they are defective in this recognition event. By analogy, we suggest that interaction of final sigma70 with the non-template strand of the anti-ITS is required for function of this portable element, thus explaining why neither final sigma32 nor the Region 2.2 final sigma70 mutants mediate anti-function. Support for the analogy with the lambdaP(R') promoter comes from preliminary experiments suggesting that the anti-ITS, like the lambdaP(R') ITS, is bipartite.
Collapse
|
36
|
Chan CL, Annapoorna V, Roy AC, Ng SC. Balloon endometrial thermoablation--an alternative management of adenomyosis with menorrhagia and dysmenorrhoea. THE MEDICAL JOURNAL OF MALAYSIA 2001; 56:370-3. [PMID: 11732085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
A 45 years old Chinese housewife presented with menorrhagia and dysmenorrhoea due to adenomyosis failed to respond to various medical treatments. She was treated with balloon thermoablation. The total menstrual blood loss (MBL) decreased from 96.94 ml before to 37.57 ml, six months after thermoablation. The pictorial blood loss chart (PBLC) showed similar decrease in blood loss. Dysmenorrhoea was also cured. At three year follow up, there was no recurrence. This is the first report which shows thermoablation decreases MBL objectively and can be tried to treat adenomyosis.
Collapse
|
37
|
Yiangou Y, Facer P, Baecker PA, Ford AP, Knowles CH, Chan CL, Williams NS, Anand P. ATP-gated ion channel P2X(3) is increased in human inflammatory bowel disease. Neurogastroenterol Motil 2001; 13:365-9. [PMID: 11576396 DOI: 10.1046/j.1365-2982.2001.00276.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
P2X(3) is a novel ATP-gated cation channel that is selectively expressed by small-diameter sensory neurones in rodents, and may play a role in nociception by binding ATP released from damaged or inflamed tissues. We have studied, for the first time, P2X(3) immunoreactivity in human inflammatory bowel disease, using Western blotting and immunohistochemistry. A major 66-kDa specific protein was found by Western blotting in all colon extracts. In the inflamed group there was a significant two-fold increase in the relative optical density of the 66-kDa band (21.2 +/- 3.1; n=8) compared to controls (11.4 +/- 3.7; n=8; P=0.009). In the control colon, P2X(3)-immunoreactive neurones were scattered throughout the myenteric and submucosal plexuses, with some neurones showing immunopositive axons/dendrites. The pattern of immunostaining was similar to the neuronal marker peripherin. In general, the intensity of the staining was greater in myenteric than submucosal neurones. The number of P2X(3)-immunoreactive neurones was significantly increased in the myenteric plexus of inflamed colon compared to controls (n=13; P=0.01). In humans, unlike rodents, P2X(3) is thus not restricted to sensory neurones. Increased P2X(3) in inflamed intestine suggests a potential role in dysmotility and pain, for which it represents a new therapeutic target.
Collapse
|
38
|
Yiangou Y, Facer P, Dyer NH, Chan CL, Knowles C, Williams NS, Anand P. Vanilloid receptor 1 immunoreactivity in inflamed human bowel. Lancet 2001; 357:1338-9. [PMID: 11343743 DOI: 10.1016/s0140-6736(00)04503-7] [Citation(s) in RCA: 268] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vanilloid receptor 1 (VR1) is expressed by sensory neurons. Once activated, these neurons evoke the sensation of burning pain and release neuropeptides that induce neurogenic inflammation. We used immunoblotting and immunostaining to estimate the density of VR1 in colonic tissues of patients with inflammatory bowel disease and of controls. Our study results indicate that VR1 immunoreactivity is greatly increased in colonic nerve fibres of patients with active inflammatory bowel disease. Thus, the discovery of new drugs that can bind the VR1 receptor, or antagonise endogenous inflammatory substances that activate this receptor, could lead to new therapies for pain and dysmotility.
Collapse
|
39
|
Lau HY, Chan CL. Modulation of intracellular cyclic AMP in immunologically activated rat peritoneal mast cells by prostaglandin D2. Inflamm Res 2001; 50 Suppl 2:S61-2. [PMID: 11411605 DOI: 10.1007/pl00022409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
40
|
Chan CL, Scott SM, Knowles CH, Lunniss PJ. Exaggerated rectal adaptation - another cause of outlet obstruction. Colorectal Dis 2001; 3:141-2. [PMID: 12791009 DOI: 10.1046/j.1463-1318.2001.00222.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
|
41
|
Li W, Chan CL, Lueng HW. Liquid chromatography-atmospheric pressure chemical ionization mass spectrometry as a tool for the characterization of anthraquinone derivatives from Chinese herbal medicine. J Pharm Pharmacol 2000; 52:723-9. [PMID: 10875550 DOI: 10.1211/0022357001774408] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
We have examined the anthraquinone derivatives of a Chinese herb medicine 'Rhubarb' by using HPLC/MS/MS, equipped with an atmospheric pressure chemical ionization source. The simultaneous determination of five ingredients in the sample extracts by HPLC/MS/MS was demonstrated. Product ion spectra of these components in the extracts were obtained and matched against known standards. Concentrations of these active ingredients were estimated by multiple reaction monitoring in the negative ion mode using a single HPLC run.
Collapse
|
42
|
Chan CL, Ray SA, Dourado R, Burnand KG. Fogarty balloon dilatation for intraoperative arterial spasm. Eur J Vasc Endovasc Surg 2000; 19:662-4. [PMID: 10873736 DOI: 10.1053/ejvs.1999.1062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE to describe an intraoperative technique using a Fogarty balloon to treat arterial spasm following vascular bypass and endarterectomy. DESIGN prospective case control study. SUBJECTS AND TREATMENT twenty-two patients following femorodistal bypass surgery and one patient following carotid endarterectomy, with arterial spasm in the distal run-off on completion angiography, were treated with Fogarty balloon dilatation. MATERIALS Fogarty balloon catheter (Baxtertrade mark). RESULTS twenty-three patients (100%) with arterial spasm were successfully treated by Fogarty balloon as demonstrated on completion angiography. No complications were seen. CONCLUSION this simple technique removes vascular spasm rapidly and produces an excellent angiographic result.
Collapse
|
43
|
Yu CL, Fielding R, Chan CL, Tse VK, Choi PH, Lau WH, Choy DT, O SK, Lee AW, Sham JS. Measuring quality of life of Chinese cancer patients: A validation of the Chinese version of the Functional Assessment of Cancer Therapy-General (FACT-G) scale. Cancer 2000; 88:1715-27. [PMID: 10738232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
BACKGROUND Few cancer specific quality-of-life (QoL) measures from the West have been translated for use with Chinese-speaking patients, and no substantial validation of these translations with adequately large cohorts has been published previously, to the authors' knowledge. The Functional Assessment of Cancer Therapy-General (FACT-G) is a well-validated QoL instrument that is specific to cancer patients. The scale was translated into Chinese and the psychometric properties of this translated scale (FACT-G [Ch]) were tested with a Chinese sample in Hong Kong, China. METHODS A total of 1262 Chinese cancer patients were selected in 3 samples from 5 Hong Kong regional hospitals. Quantitative and qualitative data were used to assess the cultural equivalence, factor structure, reliability, and validity of the FACT-G (Ch). RESULTS Focus group discussions indicated that the FACT-G was seen as covering QoL domains identified as important and relevant to Chinese cancer patients, though in some respects it was seen as having limited scope in this sample. Psychometrically, the factor structure of the FACT-G deviated from that of the original work. The FACT-G (Ch) had acceptable reliability (Cronbach alpha 0.85). The convergent validity of the FACT-G (Ch) with a generic QoL measure (WHOQOL-BREF[HK]) was 0.72 (P < 0.001), and divergent validity showed low correlations of less than 0.15 (P < 0.05) with non-QoL measures. CONCLUSIONS Focus group data indicated that the FACT-G translation into Chinese was seen as a conceptually relevant and moderately sufficient QoL measure. Psychometrically, the instrument had acceptable properties, but conceptual differences from the original version were suggested. Although more work is needed to increase its adequacy, the translated scale has reasonable utility for use with Chinese populations in clinical settings.
Collapse
|
44
|
Chan CL, Ray SA, Taylor PR, Fraser SC, Giddings AE. Endoleaks following conventional open abdominal aortic aneurysm repair. Eur J Vasc Endovasc Surg 2000; 19:313-7. [PMID: 10753698 DOI: 10.1053/ejvs.1999.1046] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE to describe the complication of <<<<endoleak>>>> following conventional open abdominal aortic aneurysm (AAA) repair. DESIGN prospective case study. SETTING two specialist vascular surgical centres. PATIENTS AND METHODS six patients who had successful conventional open AAA repair. RESULTS six patients presented with back or abdominal pain or hypotension between one and eighteen months later. An endoleak at the distal anastomosis was noted in five of the cases and one endoleak at the proximal anastomosis. All six cases were successfully repaired; two of these patients required Dacron graft replacement, whilst in four cases only direct resuturing was needed. There was no evidence of infection. CONCLUSIONS an endoleak is not a phenomenon confined to stent grafts. It should be considered in all patients who present with back or abdominal pain within eighteen months of open AAA repair. The combination of computed tomography (CT) scan and digital subtraction angiography is most useful for preoperative diagnosis.
Collapse
|
45
|
Chan CL, Jones RL, Lau HYA. Characterization of prostanoid receptors mediating inhibition of histamine release from anti-IgE-activated rat peritoneal mast cells. Br J Pharmacol 2000; 129:589-97. [PMID: 10711359 PMCID: PMC1571858 DOI: 10.1038/sj.bjp.0703072] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Prostanoid receptors mediating inhibition of anti-IgE induced histamine release from rat peritoneal mast cells have been characterized pharmacologically. PGD2 and the specific DP receptor agonists BW 245C and ZK 118182 were the most potent inhibitors with half-maximal concentrations of 0.26, 0.06 and 0.02 microM respectively. The maximum inhibition attainable was 60-65% with 10(-5) M BW 245C and ZK 118182. 2. Among several EP receptor agonists investigated, only PGE2 and the EP2/EP3 receptor agonist misoprostol induced significant inhibition (46.8 +/- 4.7% at 10(-4) M and 18.7 +/- 6.8% at 10(-5) M respectively). The IP receptor agonists cicaprost and iloprost were both less potent than the DP agonists in inhibiting histamine release (45.2 +/- 3.3% and 35.1 +/- 2.5% inhibition respectively at 10(-5) M), whereas PGF2 alpha and the TP receptor agonist U-46619 were only marginally effective. 3. The EP4/TP receptor antagonist AH 23848 failed to affect the inhibitory actions of PGD2 or PGE2 even at 10(-5) M, whereas the DP/EP1/EP2 receptor antagonist AH 6809 slightly enhanced the effect of PGD2 at 10(-6) M. 4. At concentrations of 3 x 10(-6) to 10(-5) M, the putative DP receptor antagonist ZK 138357 dose-dependently suppressed the inhibitory activities of the DP agonists, PGE2 and cicaprost. The antagonism of ZK 138357 against the DP receptor agonists appeared to be competitive with pA2 values of around six. 5. In conclusion, these data support our earlier proposal that an inhibitory DP receptor is the predominant prostanoid receptor in rat peritoneal mast cell. The properties of this receptor in relation to putative DP receptor subtypes reported in the literature are discussed.
Collapse
|
46
|
Golder M, Chan CL, O'Shea S, Corbett K, Chrystie IL, French G. Potential risk of cross-infection during peripheral-venous access by contamination of tourniquets. Lancet 2000; 355:44. [PMID: 10615896 DOI: 10.1016/s0140-6736(99)04051-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We found that a high proportion of reusable tourniquets are contaminated with blood and bacterial pathogens. Their use contravenes hospital cross-infection control protocols and we therefore recommend the use of disposable tourniquets.
Collapse
|
47
|
Sharp MM, Chan CL, Lu CZ, Marr MT, Nechaev S, Merritt EW, Severinov K, Roberts JW, Gross CA. The interface of sigma with core RNA polymerase is extensive, conserved, and functionally specialized. Genes Dev 1999; 13:3015-26. [PMID: 10580008 PMCID: PMC317155 DOI: 10.1101/gad.13.22.3015] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/1999] [Accepted: 10/05/1999] [Indexed: 11/24/2022]
Abstract
The sigma subunit of eubacterial RNA polymerase is required throughout initiation, but how it communicates with core polymerase (alpha(2)betabeta') is poorly understood. The present work addresses the location and function of the interface of sigma with core. Our studies suggest that this interface is extensive as mutations in six conserved regions of sigma(70) hinder the ability of sigma to bind core. Direct binding of one of these regions to core can be demonstrated using a peptide-based approach. The same regions, and even equivalent residues, in sigma(32) and sigma(70) alter core interaction, suggesting that sigma(70) family members use homologous residues, at least in part, to interact with core. Finally, the regions of sigma that we identify perform specialized functions, suggesting that different portions of the interface perform discrete roles during transcription initiation.
Collapse
|
48
|
Maskarinec G, Chan CL, Meng L, Franke AA, Cooney RV. Exploring the feasibility and effects of a high-fruit and -vegetable diet in healthy women. Cancer Epidemiol Biomarkers Prev 1999; 8:919-24. [PMID: 10548322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Based on reports that fruits and vegetables may protect against breast cancer, this randomized intervention study tested the feasibility of increasing fruit and vegetable intake among healthy women to 9 daily servings through individual dietary counseling and group activities. Adherence to the dietary recommendations was monitored by 24-h food recalls, log sheets, and plasma carotenoid assessments. To explore possible cancer protective mechanisms of fruits and vegetables, we investigated the treatment effect on plasma phenol levels and on thiobarbituric acid-reactive substances measured as malondialdehyde equivalents, a possible marker of oxidative damage. At baseline, women in the intervention (n = 13) and control (n = 16) group reported an average daily consumption of 3.3 and 3.2 fruit and vegetable servings, respectively. After 3 and 6 months of intervention, intake in the intervention group had increased to 8.3 and 7.4 servings, whereas the control group reported an average of 4.2 and 4.1 daily servings. An increase of plasma carotenoid levels from 1249 microg/liter at baseline to 1854 and 1827 microg/liter after 3 and 6 months confirmed compliance with the dietary recommendations in the intervention group. Plasma carotenoid levels among controls changed slightly from 1165 to 1231 and 1291 microg/liter Whereas total phenol levels did not respond according to our hypothesis, malondialdehyde levels decreased slightly in the intervention group. These results suggest that motivated women can substantially increase their fruit and vegetable intake, which leads to a notable increase in plasma carotenoid levels.
Collapse
|
49
|
Chan CL, Lau HY. Prostanoid DP receptor activation inhibits anti-IgE induced histamine release from rat peritoneal mast cells. Inflamm Res 1999; 48 Suppl 1:S29-30. [PMID: 10350148 DOI: 10.1007/s000110050384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
50
|
Gustafson DH, Hawkins R, Boberg E, Pingree S, Serlin RE, Graziano F, Chan CL. Impact of a patient-centered, computer-based health information/support system. Am J Prev Med 1999; 16:1-9. [PMID: 9894548 DOI: 10.1016/s0749-3797(98)00108-1] [Citation(s) in RCA: 347] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Consumer health information systems potentially improve a patient's quality of life and activate patient self-care. OBJECTIVES Test a computerized system (CHESS: Comprehensive Health Enhancement Support System), which, in this application, provided HIV-positive patients with information, decision support, and connections to experts and other patients. Would patients given in-home access to computers use the system, improve their quality of life, reduce health-risk behaviors, and use medical services more efficiently? RESEARCH DESIGN Randomized controlled trial: CHESS computers in experimental subjects' homes in Madison or Milwaukee, Wisconsin, for 3 or 6 months; controls received no intervention. Subjects were compensated for self-report surveys completed before, during, and after CHESS installation. SUBJECTS Of 204 HIV-positive patients recruited (90% male, 84% white, average education some college, and 65% experiencing HIV-related symptoms), 90% completed the study. MEASURES Self-reports of quality of life and frequency and duration of use of medical services. RESULTS CHESS was used daily with little difference between demographic subgroups. While CHESS was in the home, its users reported quality-of-life improvements: active life, negative emotions, cognitive function, social support, and participation in health care. They also reported spending less time during ambulatory care visits, making more phone calls to providers, and experiencing fewer and shorter hospitalizations. CONCLUSIONS A computer-based personal health support system can improve a patient's quality of life and promote more efficient use of health care.
Collapse
|